diff --git a/public/assets/pages/viewerpage/application_downloader.js b/public/assets/pages/viewerpage/application_downloader.js
index 6918d6e0..7f0073cc 100644
--- a/public/assets/pages/viewerpage/application_downloader.js
+++ b/public/assets/pages/viewerpage/application_downloader.js
@@ -9,7 +9,7 @@ import { transition, getFilename, getDownloadUrl } from "./common.js";
 import "../../components/icon.js";
 import "./component_menubar.js";
 
-export default async function(render) {
+export default async function(render, { acl$ }) {
     const $page = createElement(`
         <div class="component_filedownloader">
             <component-menubar></component-menubar>
@@ -41,6 +41,7 @@ export default async function(render) {
         })),
         rxjs.tap(() => setLoading(false)),
     ));
+    effect(acl$);
 }
 
 export function init() {
diff --git a/public/assets/pages/viewerpage/model_files.js b/public/assets/pages/viewerpage/model_files.js
index 235f3d51..dafb0392 100644
--- a/public/assets/pages/viewerpage/model_files.js
+++ b/public/assets/pages/viewerpage/model_files.js
@@ -1,12 +1,23 @@
+import { toHref, navigate } from "../../lib/skeleton/router.js";
 import rxjs from "../../lib/rx.js";
 import ajax from "../../lib/ajax.js";
-import { getCurrentPath } from "./common.js";
+import { AjaxError } from "../../lib/error.js";
 import { forwardURLParams } from "../../lib/path.js";
+import { getCurrentPath } from "./common.js";
 
 export const options = () => ajax({
     url: forwardURLParams(`api/files/cat?path=${encodeURIComponent(getCurrentPath())}`, ["share"]),
     method: "OPTIONS",
-}).pipe(rxjs.map((res) => res.responseHeaders.allow.replace(/\r/, "").split(", ")));
+}).pipe(
+    rxjs.catchError((err) => {
+        if (err instanceof AjaxError && err.err().status === 401) {
+            navigate(toHref("/login?next=" + location.pathname + location.hash + location.search));
+            return rxjs.EMPTY;
+        }
+        throw err;
+    }),
+    rxjs.map((res) => res.responseHeaders.allow.replace(/\r/, "").split(", ")),
+);
 
 export const cat = () => ajax({
     url: forwardURLParams("api/files/cat?path=" + encodeURIComponent(getCurrentPath()), ["share"]),